When Linford said "I'm not in any way condoning the threats the driver made", there is no reason to suppose that is not exactly what he meant. This wording seems to fit perfectly with his other statements.
Except for his continual repetition of the phrase "six of one ..." which if it means anything at all means that Matt was equally to blame. The number "six" and the quantity "half a dozen" are, as I expect you know, equal to each other, and the phrase is therefore generally used when both parties to some interaction are held to be "as bad as each other"
While I'm sure that most or all of us will agree that Matt would have been less likely to escalate the situation had he not e.g. read the car numberplate out, the use of the word "escalate" is itself a honking great clue that the offences and insults occasioned in the first half, wherein Matt impugns the driver's ability to go round corners properly, are not in fact of the same magnitude as those in the second half, where the driver cuts him up and then threatens physical violence against him.
It is of course possible that Linf is perhaps
not aware how large the archaic unit "a dozen" is, and is just using the phrase to mean "there was some degree of blame on both sides", but as that is not what the phrase means, this is not how he comes across. Here I can only echo your own advice that "language [...] should be couched very carefully"